Previews never really updating (Quarto + Python + Shiny + Jupyter)

[mmchugh87]

Description

Hi there.

I'm on a windows machine.
Python 3.
Recent version of Shiny.
quarto-1.4.554-win.
I have installed the Jupyter-Quarto extension via jupyterlab extension manager.

I'm trying to develop my skills at building Shiny dashboards.

I have a very unremarkable Jupyter notebook, I've called it "penguin_jupyter.ipynb".
It is basically a duplicate of the same content you will find in the Quarto penguin dashboard example.
Albeit, the opening lines in my case are these:

---
title: "Dirty Penguinz"
author: "Codswollop"
format: dashboard
server: shiny
execute: 
  enabled: true
---

I run the following line in a Terminal:

quarto preview penguin_jupyter.ipynb

The response in the terminal seems to be free from error. It looks like this:

Starting python3 kernel...Done

Executing 'penguin_jupyter.ipynb'
  Cell 1/6: ''...Done
  Cell 2/6: ''...Done
  Cell 3/6: ''...Done
  Cell 4/6: ''...Done
  Cell 5/6: ''...Done
  Cell 6/6: ''...Done

pandoc 
  to: html
  output-file: penguin_jupyter.html
  template: >-
    C:\Users\maste\AppData\Local\Programs\Quarto\share\formats\dashboard\template.html
  standalone: true
  section-divs: true
  html-math-method: mathjax
  wrap: none
  default-image-extension: png
  
metadata
  document-css: false
  link-citations: true
  date-format: long
  lang: en
  page-layout: custom
  title: Dirty Penguins
  author: Codswollop
  server:
    type: shiny
  remove-hidden: all
  
Output created: penguin_jupyter.html

If I make a trivial change to the jupyter file, and save it, I would hope the change would be reflected in the preview (which I am viewing on "localhost" using Chrome browser). However the changes are never reflected there. I have tried hitting refresh, and clearing the browser cache, but It doesn't help.

The strange thing is, I can see that the output html (penguin_jupyter.html) is in fact adopting the changes I am making to the jupyter file... but this is not sufficient for the preview in the browser to be updated.

Can anyone assist? I have seen one discussion here that was only somewhat similar (#9202). I have also been looking at the Quarto Jupyter guide and it implies that my preview should be updating.

Many thanks

[mcanouil]

Could you properly format your post using code blocks for code and terminal outputs? Thanks.
If your code contains code blocks, you need to enclose it using more backticks, i.e., usually four ````.

See https://quarto.org/bug-reports.html.

[mmchugh87]

Incidentally, I experience the same issue with Quarto Pre-release — v1.5.39.

What tends to happen is, to visualise any changes I have made in the Jupyter notebook, it seems I need to save the file with a new name and then open another terminal instance and preview the new file.

I end up with many, many terminal instances running simultaneously (I cannot terminate them no matter what I try).

If I try to preview the same file via two different terminal instances, I encounter errors (hence I have been changing the file names).

If I can get the preview feature working correctly, it will enormously increase the speed at which I can learn how Quarto / Shiny / Python work together.

[cderv]

We currently have a problem in our windows builds with preview

• quarto-preview.js Not Found In Quarto 1.4.554 #9574

This is probably related.

We'll fix soon. Sorry for the trouble.

[mmchugh87]

thanks.
I have been playing around with quarto for the last 72 hours (including uninstalling, reinstalling, different versions).
I definitely encountered the missing "quarto-preview.js" error a day or two again but I cannot reproduce it now.
And I don't encounter that error anymore (but preview nonetheless does not work).

No idea if it is helpful to know but in my area here:
C:\Users\maste\AppData\Local\Programs\Quarto\share\preview
I have the file "quarto-preview" albeit it is a "chrome HTML document".